In the refractories industry, the term “precast shapes” has been adopted to refer to articles made from castable materials that are supplied to an end user in a form or shape ready to be installed where used. Some precast refractory shapes are designed to be embedded within a surrounding refractory material. An example of such a precast refractory shape is a well block that is used in a ladle bottom. The well block is typically placed in a ladle bottom, and a refractory material is cast thereabout. To insure that the well block is secured within the surrounding cast material, it is conventionally known to form an outwardly-extending, annular flange. When the well block is placed into the ladle bottom and the refractory material is cast thereabout, the flange or projection extends into the surrounding castable, thereby holding the well block in place once the surrounding castable has set.
It is also known to form the well block to have a slightly conical shape, wherein the lower end of the block is slightly larger than the upper end of the block. The taper on the well block acts as a locking mechanism to prevent upward movement of the precast shape once the surrounding castable is in place.
A problem with the foregoing designs and methods of locking precast shapes into a surrounding refractory is that a flange or protrusion disposed around the lower end of a precast shape does not prevent portions above the flange from separating and floating upwardly should cracks develop in the refractory shape above the flange or protrusion. Tapered shapes may prevent separation of cracked shapes, but tapered shapes are not suitable in all applications.
The present invention overcomes these and other problems and provides a precast refractory shape having surface means for fixedly securing the precast shape in a surrounding refractory material and a method of forming same.